package main

import (
	"fmt"
	"github.com/gin-gonic/gin"
	"log"
	"net/http"
	"strings"
)

func main() {

	engine := gin.Default()
	engine.Use(Cors())

	engine.Handle("POST", "/login", func(context *gin.Context) {
		fmt.Printf(context.FullPath())
		username := context.PostForm("username")
		passwd := context.PostForm("passwd")
		fmt.Println(username + "  " + passwd)
		_, _ = context.Writer.Write([]byte(username + "????" + passwd))

	})

	engine.POST("/lg", func(context *gin.Context) {
		mess := context.DefaultPostForm("mess", "some_information")
		fmt.Println(mess)
		_, _ = context.Writer.Write([]byte("post " + mess))
	})

	engine.GET("/user/:id", func(context *gin.Context) {
		id := context.Param("id")
		if true {
			fmt.Println(id)
			_, _ = context.Writer.Write([]byte(id))
		}
	})
	//get url params

	engine.GET("/he", func(context *gin.Context) {
		fmt.Printf(context.FullPath())
		_, _ = context.Writer.Write([]byte("Hello from masaikk!"))
	})

	engine.Handle("GET", "/hand", func(context *gin.Context) {
		fmt.Printf(context.FullPath())

		name := context.DefaultQuery("name", "someone")
		//get the param in get request

		_, _ = context.Writer.Write([]byte("hello " + name))
	})

	if err := engine.Run(":8090"); err != nil {
		log.Fatal(err.Error())
	}

}

func Cors() gin.HandlerFunc {
	return func(c *gin.Context) {
		method := c.Request.Method               //请求方法
		origin := c.Request.Header.Get("Origin") //请求头部
		var headerKeys []string                  // 声明请求头keys
		for k, _ := range c.Request.Header {
			headerKeys = append(headerKeys, k)
		}
		headerStr := strings.Join(headerKeys, ", ")
		if headerStr != "" {
			headerStr = fmt.Sprintf("access-control-allow-origin, access-control-allow-headers, %s", headerStr)
		} else {
			headerStr = "access-control-allow-origin, access-control-allow-headers"
		}
		if origin != "" {
			c.Writer.Header().Set("Access-Control-Allow-Origin", "*")
			c.Header("Access-Control-Allow-Origin", "*")                                       // 这是允许访问所有域
			c.Header("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE,UPDATE") //服务器支持的所有跨域请求的方法,为了避免浏览次请求的多次'预检'请求
			//  header的类型
			c.Header("Access-Control-Allow-Headers", "Authorization, Content-Length, X-CSRF-Token, Token,session,X_Requested_With,Accept, Origin, Host, Connection, Accept-Encoding, Accept-Language,DNT, X-CustomHeader, Keep-Alive, User-Agent, X-Requested-With, If-Modified-Since, Cache-Control, Content-Type, Pragma")
			//				允许跨域设置																										可以返回其他子段
			c.Header("Access-Control-Expose-Headers", "Content-Length, Access-Control-Allow-Origin, Access-Control-Allow-Headers,Cache-Control,Content-Language,Content-Type,Expires,Last-Modified,Pragma,FooBar") // 跨域关键设置 让浏览器可以解析
			c.Header("Access-Control-Max-Age", "172800")                                                                                                                                                           // 缓存请求信息 单位为秒
			c.Header("Access-Control-Allow-Credentials", "false")                                                                                                                                                  //	跨域请求是否需要带cookie信息 默认设置为true
			c.Set("content-type", "application/json")                                                                                                                                                              // 设置返回格式是json
		}

		//放行所有OPTIONS方法
		if method == "OPTIONS" {
			c.JSON(http.StatusOK, "Options Request!")
		}
		// 处理请求
		c.Next() //	处理请求
	}
}
